Does the 'no 'poo' method really work?

Advocates of the so-called ‘no poo’ movement forgo conventional soapy detergents such as shampoo and conditioner.

Instead, they wash their hair with only with water, or use natural ingredients such as rye flour, vinegar, raw eggs, porridge and chalk on their hair.

Celebrity fans including Kim Kardashian, Shailene Woodley, Adele, Gwyneth Paltrow and Jessica Simpson say they delay washing their hair for days, weeks and even months on end – but some use shampoo during rare washes.

Some worry the chemicals in shampoo are damaging to their hair and scalp, while others embark on the regime to save time - or because they believe it simply makes their hair look and feel better.

But Carol Walker, a trichologist from the Birmingham Trichology Centre, has previously warned that while the ‘no poo’ method leads to healthy, glossy hair for some people, it can cause spots and exacerbate skin problems in others.

She told MailOnline: ‘Vinegar, eggs, dry shampoo – which is made from chalk - have been used for decades to clean hair. They just absorb the grease.

Some of these products, however, could dry out the scalp and make conditions such as dandruff, eczema and dermatitis worse, she said.

And for people with naturally oily skin, going without shampoo may trigger or worsen acne.

‘If you are susceptible to spotty skin, leaving your hair to go oily can lead to spots on the scalp and around the hairline and can re-infect spots or eczema. This can then cause a secondary infection.'